In the past many different products and processes have been tried in an attempt to prevent the build-up of marine organisms such as barnacles, zebra mussels and the like on the surfaces of underwater objects such as boat hulls, docks and water supply intake pipes. This has been a problem both in salt water in the oceans and in fresh water such as that found in the Great Lakes.
One example of such prior art anti-fouling device is shown in U.S. Pat. No. 3,497,990 issued to F. A. Jeffries in which a layer of foam material having interconnected cells is used as a storage layer for anti-fouling compounds such as bis (tri-n butyl tin oxide) which slowly seeps out through a permeable outer cover layer to prevent the growth of marine organisms on any underwater surface to which it is attached.
Well known anti-fouling paints are also frequently used with varying degrees of success. One of the primary defects of such paints is the short foul-free life. Secondly the paints lack durability and have low abrasion resistance. Many paints have unfavorable compatibility with the surfaces on which they are used and tend to magnify electrolytic corrosion when used over metallic surfaces
U.S. Pat. No. 3,761,334 issued to K. Zondek shows another approach to the anti-fouling problem in which copper foil is attached to a boat hull with adhesive.
Other patents such as U.S. Pat. No. 3,142,283 issued to T. A. Fisher show a boat hull enclosed by a loose cover which has either fresh water or chemical inhibitor pumped into the space between the cover and the hull. While such a concept might be used with a moored boat it would not be practical to use with a moving boat.
My copending patent application Ser. No. 754,069 filed Sep. 3, 1991 which is now abandoned discloses a removeable waterproof cover for anti-fouling protection which can be easily removed and replaced if the need arises. This invention is a further development from the invention in my prior application.